Neumann M49V tube mistery...

[OneRoomStudio]

They really copy everything you post here too

No, I haven't disappeared. I had only changed my alias, but kept the account.

After many tests I can now report that it doesn't matter which triode you use. I have not been able to detect any differences between the various 6S6Bs. The design used by Neumann has a higher internal insulation resistance, which is better in principle. But practically it doesn't matter. These tubes produce very little noise and are all mechanically insensitive. But other Soviet triodes also proved to be suitable replacements. One even better than the 6S6B or the 6S3B. There will therefore be enough replacements for defective AC701s over the next 50 years.

I’m curious which on you thought was even better! Also, have you had the chance to try other triodes, such as the EC71?

 

[k brown]

They really copy everything you post here too

No, I haven't disappeared. I had only changed my alias, but kept the account.

After many tests I can now report that it doesn't matter which triode you use. I have not been able to detect any differences between the various 6S6Bs. The design used by Neumann has a higher internal insulation resistance, which is better in principle. But practically it doesn't matter. These tubes produce very little noise and are all mechanically insensitive. But other Soviet triodes also proved to be suitable replacements. One even better than the 6S6B or the 6S3B. There will therefore be enough replacements for defective AC701s over the next 50 years.

I have long maintained that the tube is the very last thing responsible for the sound of the M 49 (and M 50). I found people's absolute obsession with the AC701 rather amusing.

 

[Menschmeier]

I’m curious which on you thought was even better! Also, have you had the chance to try other triodes, such as the EC71?

I have not tested the EC71, but it works with a higher heating voltage. Others have been using them for years. The DC762, for example, works in a triode circuit from 1 volt, but it is 2 cm longer. The Soviet military tubes all work with 4 volts. They are the most suitable. I don't want to publish a recommendation, that would only spoil the prices. Unfortunately, this has already happened with the 6S6B. I therefore had to import mine from Russia in a complicated process.

 

[Menschmeier]

I have long maintained that the tube is the very last thing responsible for the sound of the M 49 (and M 50). I found people's absolute obsession with the AC701 rather amusing.

I agree with that. The capsule, the basket and to some extent the transformer are responsible for the sound. The circuit also plays a role. The tube, on the other hand, only plays a role in exceptional cases. With the U47/48, for example. Unfortunately, there is no suitable replacement tube for the VF14. Here I would switch to the replacement circuit from Andreas. His technician continues to build them.